Method of plasticizing proteins and products thereof



- than plasticized protein compositions at Patented Jan. 27, 1948 METHODOF PLASTICIZING PROTEINS AN PRODUCTS THEREOF Richard Paul Carlton andHoward C. Brinker,

St. Paul, Minn., assignors to Minnesota lilining & ManufacturingCompany, St. Paul, Mmrn, a

corporation of Delaware 7 No Drawing. Application February 22, 1943,

Serial No. 476,762

1 v This invention relates to the treatment of prolStJlaims. (Cl.106-161 teins; more particularly to the plasticizing of 1 proteins orprotein-dike materials, especially polyamides, to render them flexible,without regard to their moisture content.

This application is a continuation-in-part of our copending applicationSerial No. 179,332, filed December 11, 1937, now abandoned.

The plasticizers for proteins of the character of glue, casein, etc.,known to the art are the polyhydric alcohols, alkali metal salts ofsulfuric acid esters of higher alcohols or fatty oils-such as Turkey redoil, glycerine and the like. Their inherent characteristics are suchthat they depend mainly upon their hygroscopicity for their plasticizingaction, and it may be seen that proteins plasticized, as with the aboveingredients, will tend to become hard and dry under arid or semi-aridconditions.

It is therefore an object of this invention to provide a plasticizerwhich will render a protein substance flexible irrespective of its watercontent.

Furthermore, our improved plasticized protein composition is more stableat high temperatures present available.

Broadly setting forth our invention in general terms, we have discoveredhow to produce a plasticized protein composition which will remainflexible and plastic in the absence of moisture in the ambientatmosphere. These plasticized materials may be formed into sheets orfilms, and

transparent sheeted compositions of this type can be produced inaccordance herewith. While certain other substances can undoubtedly befound which can be used with and/or worked into protein or protein-likemolecules to accomplish the results herein described, we have foundcertain materials which provide this new and useful result. This result,to the'best of our knowledge, was heretofore unattained by any means ormethod: see "Casein and Its Industrial Applica-.

tions by Sutermeister and Browne, published by the Reinhold PublishingCorp. in 1939, i. e. sub- 7 and summer heat.

2 (CH3CONHCH2OH) have been found to be very satisfactory as proteinplasticizers, especially the formanilide.

Of the amines, phenylbenzylamine (CsHsNHCHzCeHs) and cyclohexylamine(CsHiiNHz), have been found to be fairly satisfactory for this purpose,but, with the possible exception of phenylbenzylamine, they are quitevolatile and prove most successful when the plasticized proteinsubstance is to be used immediately after plasticization or shortlythereafter, or where this plasticized material may be stored in suitablecontainers or,

under pressure for future use. It will be apparent, however, thatmaterials which are volatile under room or atmospheric conditions cannotin any event serve to yield a composition which, e. g. in the form of afilm, sheet orwrapping, will remain flexible and plastic when exposed toan ambient atmosphere at such temperatures, and in the absence ofmoisture. v

Ethylene diamine diethanol, ethylene diamine tetraethanol, salicanilide,glycanilide, and phenyl glycol amine (CsHsNI-ICHOHCHzOH), have also beenfound to have some utility in this connection, although formanilide ispreferable thereto. Of these materials glycanilide and sallcanilide arepreferred, for one reason because they are stable and non-volatile underroom temperatures The amino alcohols in general are quite volatile,while derivatives of phenyl glycine are not stable and therefore provemost satisfactorywhen'used as stated in the foregoing paragraph.

of the amino sodium sulphonates, phenylmethyleneamine sodium sulphonate(CsHsNHCHaOSOzNfl) phenyl octylene amine sodium sulphonate(CqHsNHCaHwOSOzNal phenyl isopropyleneamine sodium" sulphonate (CeH5NHC(CHa)sOSO2Na) and phenyl methylene amine sodium sulflnate 3 the like.have the property of rendering the protein flexible even when no wateris present. More specifically. for example. iormanilide or derivatives oformanilide, will plasticize proteins so that a ture of protein andformanilide is flexible when dry under ordinary atmospheric conditions.I

These and other materials of this character will plasticize the proteinsubstance when completely dry,. but some of them act more readily whenthe protein contains a small percentage of mois ure. Therefore, forsecuring the most desirable results. with materials; of the abovecharacter requiring a slight moisture content, we desire to augment ourprotein and amine derivative mixture with other substances. which may ormay not in the'iselves have a plasticizing action. However, we preferaugmenting-plasticizer agents of the type of Turkey red oil. Likewise,these augmenting substances may be the am. monia, substituted ammoniasuch as triethanolamine or alkali'metal salts of the acid sulfuric acidester of higher alcohols, fatty oils, fatty oil acids. and the like.Compounds containing more than one hydroxyl group per molecule may alsobe used as augmenting agents, as for example Protein 35 .Formanilide 38Turkey red oil or for securing a fairly flexible treated material, weprepare a composition by suitable mixing conslsting of the following inapproximate proportionate parts:

Parts Protein 40 Formanilide 80 Turkey red oi diethyleneglycol glycerol,or similar compounds.

For example. other augmenting agents which 'may be employed are, fattyalcohols, fatty oils or fatty oil acids which may be combined withphosphoric acid to form an acid ester. This ester may be combined withan alkali metal, ammonia or or anic base to form a product that may beused in place of a similar one made using a suifuric acid ester such asTurkey red oil,

In practice, plasticizing proteins of a character as herein set forth bymeans of various amides or substituted amines with or without theaddition of augmenting agents may be accomplished by addition of theplasticizing and/or augmenting agents to a. dehydrated protein. However,we preferably swell the proteins with water for more readily securingplastioizatlon of the protein, as a hydrated protein is more rapidlyplasticized due to the penetration of the plasticizing ingredient andaugmenting agent, if used. After application of the piasticizingsubstance. any excess water may be removed by drying the finalplasticized film under ordinary atmospheric conditions.

To better illustrate the nature of this invention, if it is desired touse protein as a coating material, film, sheet, or the like, thehardness of the coating may be varied by varying the relative proportionof the ingredients; for example, if a relatively hard finish isrequired, we may prepare our mixture in approximate proportionate partsas follows:

Parts Protein 87 Formanilide 28 Turkey red oi 4 ready for application byany suitable means as a coating or filling material.

A composition forming a fairly hard product consisting of the followingin approximate proportionate parts:

7 Parts Protein 55 Formanilide 4 Turkey red oi 10 Plasticizer In theabove formulas glycanilide or salicanilide or lactic amide may besubstituted for the formanilide with similar or parallel results. Alsoany of the group oi amides. amines, their derivatives and equivalents,as herein set forth, may be employed in lieu of some or all of theformanilide, glycanilide, etc., with correspondingly varying results;

In the above descriptions. while we have illustrated the use of varyingproportions of an augmenting ingredient, it is to be understood that wemay plasticize a glue or other protein or pro-' tein-like substance withvarious amides, amines, and their derivatives having the property ofplase ticizing the protein substances, such amides c.- substitutedamides as formaniiide, formicin, glycanilide'and the like, rendering theprotein flexible and plasticized even when no water is present.Likewise, in their use these materials or augmenting agents, as hereindisclosed, may sometimes "be aided by a reaction material or aneutralizing material in their application, as for example in some casesa reaction product may be formed between the agent and \a dextrose; or,as with triethanolamine, a castor oil free fatty acid. sulfonated, andwashed, may be used for neutralizing the triethanolamine.

A composition formed of the protein and its plasticizer without anaugmenting agent is determined by the degree of flexibility desired, asfor example when desiring a relatively hard film, we may use a greaterpercentage of protein than of its pl'asticizer, as formanilide or thelike. This composition may consist of the following in ap proximateproportionate parts:

Parts Protein 40 prepared by mixing the protein in a hydrated ordehydrated state with its Dlasticizer until the protein is thoroughlysaturated and then drying at atmospheric conditions.

As will be readily recognized. increasing or decreasing theproportionate parts of plasticizer agents of the nature herein describedwill increase or decrease the flexibility of the proteinproportionatelmand it is to be understood that mixtures as representedby the ingredients as illusible sheets of protein mixtures, fortreatments of paper. cloth, felts or'the like in the development ofshades, artificial leathers,'decorative coverings.

abrasive backings. tape backings, protective coverings, label adhesives,and many others, the composition and plasticity of the protein beingdetermined in accordance with its use. Where toxicity is' avoided, foodwrappings and the like can also be made advantageously in accordancehere-' with.

In choosing: the proper plasticizing agent of a nature as herein setforth, care must be taken to select a substance for the particular usageexpected which is not too volatile, thereby upon exposure destroying theplasticizing effect due to its evaporation, or where upon its usage theneed for plasticity is temporary. 'It is further preferable to usecompounds not strongly alkaline. and

preferably having a pH of the order of 7, e. 'g. 6.5

til-7.5.

It will be further understood that ii ,desiredthe' protein 'plasticizedcompositions as herein dement with acetaldehyde or formaldehyde or othertanning agents in the usual manner as practiced by the trade for'thetreatment of a protein substance.

We have also employed various 'of our plasticizing agents to plasticizenylon," a linear polyamide manufacturedby E. I. du Pont de Nemours 8:00., Wilmington, Delaware, and described in various U. S. patents suchas various of the patents of Wallace H. Carothers, illustrative of whichare Nos. 2,071,251 and 2,071,253.

One illustration of our procedure for improving the flexibility or nyloninvolved employing Parts Nylon 3% Phenol, 90% (as solvent) 12Formanilide 0.3

tion which we produced is:

- Parts Nylon Phenol 15 Glycanilide 0.5

The composition formed a compatible solution on warming to 100 C. Whenthe phenol .was evaporated. the resulting product was found to bescribed may be rendered water insoluble by treattaining a hydroxyl groupis joined to the carbonyl What we claim is:

1; A composition of matter. comprising a .protein plasticized with amaterial containing an ammonia derivative comprising formanilide.

2. A composition of matter comprising a protein plasticized with amaterial containing an ammonia derivative havingthe grouping in whichthe R group is an aromatic radical and the tree valence or the carbonylcarbon atom is satisfied by a radical from the group consisting of ahydrogen atom and radicals containing oxygen.

3. A composition of matter comprising a protein plasticized with amaterial comprising an ammonia derivative having the grouping.

in which X isa radical containing oxygen and R is an aromatic radical,said ammonia derivative being approximately neutral, 1. e. having a pHof the order of 7.

. 4. A composition of matter comprising a pro tein and a materialcomprising an ammonia derivative and having the grouping o v ad r inwhich R is an aryl group and a radical con carbon atom.

5. A composition of matter comprising a prov tein and a plasticizertherefor containing an aryl substituted amide having the grouping inwhich X is an aliphatic radical of low molecular weight containingoxygen and in which R is a radical from the group consisting of aromaticradicals and oxygen-containing aliphatic radicals.

6. A composition of matter compri'singa protein plasticized with amaterial containing an definitely more flexible than nylon alone, the

glycanilide being compatible with the nylonand acting as a plasticizertherefor.

Unless otherwise stated, all proportions herein are-*by weight.

In describing this invention, we have used specific ingredients tobetter illustrate the principles involved, and it is to be clearlyunderstood that our discovery of an improved plasticized proteincomposition as set forth herein is not limited to the specificingredients or proportions thereof.-

Varied compositions having the novel characteristics herein describedand/or claimed are likewise contemplated.

amide having the grouping t in which R" represents an aryl group and "x"is a radical from the group consisting oi hydrogen and oxygen-containingradicals, and said amide having a melting point at least substantiallyas low as that of formanilide.

'1. A composition oi! matter comprising a protein plasticized with amaterial containing an amide having the grouping n-1 i o x in which "13,represents an aryl group and "x" is a radical from the group consistingof hydrogen and oxygen-containing radicals, and an augmenting agent forsaid amide, said augmenting agent having a substantially lower meltingpoint than said amide and being compatible with the latter and alsobeing substantially chemically inert to said protein.

8. A composition of matter comprising a protein plasticized with amaterial containing an ammonia derivative comprising iormaniiide and anaugmenting agent for said iormanilidc, said augmenting agent eing aliquid at room temperatures and beingcompatible with said formanilideand also substantially chemically inert to said protein, saidcomposition being substantially free of crystallized iormanilide.

9. A composition of matter composed of protein and a plasticizing agent,the latter comprising a non-hygroscopic ammonia. derivative including asubstituted amide having the grouping having a melting point of theorder of that of iormanilide and being present to an extent by teinplasticized with a material containing an ammonia derivative having thegrouping R-N-C in which "R" is an aryl group and "X" is the radical"OSOrY", "Y being an alkali radical.

13. The process 01' producing a flexible protein product which comprisesplasticizing a hydrated protein with an agent containing an amidehavweight at least substantially as great as that of said augmentingagent. I

10. A flexible protein composition comprising protein plasticized with amaterial containing an ammonia derivative having the grouping Rs/ix inwhich R is an aryl group and 3" is a radical from the group consistingof hydrogen and oxygen-containing radicals of low weight and theninsoiubilized by the use of a tanning agent.

11. A composition of matter comprising a pro tein plasticized with amaterial containing an ammonia derivative comprising both an amide andan amino-alcohol, said amide and amino-alcohol both having the groupingc fi ii\ where R is an aryl group.

12. A compositionof matter comprising a proing the grouping R-N-C inwhich "R" is an aryl group, and "x" is chosen from the group consistingof oxygen-containing aliphatic radicals and hydrogen, forming theplasticized protein composition into desired shape andthen drying thsame at temperatures of the order of atmospheric temperatures.

14. A composition of matter comprising protein and a, non-hygroscopicplasticizer therefor, said plasticizer being an amide having a meltingpoint .of the order oi that of tormanilide or lower and having theformula 1 a -N -cn where R is a radical from the group consisting oiaromatic radicals and oxygen-containing aliphatic radicals, said amidebeing approximately netural, i. e. having a pH of the order of 7.

15. A new article of manufacture including a protective film comprisingprotein plasticized as defined in claim 14.

RICHARD PAUL CARLTON.

HOWARD C. BRINKER.

REFERENCES crrnn The following references are of record in. the die ofthis patent:

UNITED STATES PATENTS Number Name 1 Date 2,276,437 Vaala ..,Mar. 17,1942 1,775,175 Schmidt et al. Sept. 9, 1930 2,115,716 Hansen May 3, 19382,101,574 Dangelmaier Dec. 7, 1937 2,225,605 Lubs Dec. 17, 1940

